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Read-Only Pages

A page of memory can be marked as valid for reading but invalid for writing. Program text is marked this way because program text is read-only; it is never changed. If a process attempts to modify a read-only page, a hardware interrupt occurs. When the page is truly read-only, the kernel turns this into a SIGSEGV signal to the program. Unless the program is handling this signal the result is to terminate the program with a segmentation fault.


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